• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.47-53
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• 2011

Firstly, FEM model for the body frame of a fuel cell vehicle was built up and design optimization results based on different schemes were exhibited. One scheme was to minimize weight while maintaining the normal mode frequencies and the other was to increase the frequencies without weight change. Next, for a rear frame model, shape parameter study on collapse characteristics such as peak resistance load and absorbed energy was carried out. Also, the stiffness of frame mounting brackets was predicted using inertance calculation and the durability of those mounting brackets for vehicle system loads was evaluated. Finally, for a representative mounting model, the influence on durability due to thickness change was analyzed.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.4
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• pp.379-385
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• 2016

Door impact beam plays a key role in minimizing the occupant injury within the side impacted vehicle through preventing intrusion of the impacting vehicle. Steel pipe type door impact beam has been widely adopted since it has simple structure and the overall strength is easily determined according to the pipe size. The brackets welded at pipe ends connect the door impact beam and the door panels by spot welds. In this study, first, the effect of pipe thickness, bracket thickness and door mounting stiffness was respectively analyzed. Next, application of the tailor rolled pipe was examined and several alterations of the bracket mounting method were considered. Application of tailor rolled pipes with superior bracket mounting method showed remarkable strength enhancement and weight reduction possibility in comparison with the current door impact beam.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.4
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• pp.14-22
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• 2022

To reduce the weight of the car and ensure the safety of the driver while driving, the existing 440 MPa-class mounting bracket was treated at 590MPa to improve collision safety and secure the weight of the vehicle body. The following conclusions were drawn from the tensile test, forming analysis, and springback prediction. In the formability and springback analyses using FLD, it could be confirmed that bending was an essential process because the formability and flatness were much better when bending was added than when bending was not applied. Based on the research results, it was deduced that the mold design was necessary so that the molding was carried out at a strain rate of 20% or less for stable molding.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.5
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• pp.103-110
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• 2021

The mounting performance of the GFRP(Glass fiber Reinforced Plastic) beam and the mechanical mounting of the steel bracket was studied to be mounted as a GFRP impact beam on the side door of the passenger car. Moreover, an open-hole tensile test was performed to evaluate breakage tendency based on GFRP stacking conditions. Furthermore, the tightening strength of rivets and bolts was compared using the single lap-shear tension test for the GFRP stacking pattern. Additionally, the GFRP beam and bracket mounting features were designed; moreover, the prototype and bracket were assembled. Additionally, the bracket mounting bending test and the door assembly static bending test were performed to verify the stability of the bracket mounting. In the bracket fastening bending test, no breakage occurred in the connection part between the GFRP beam and the bracket, and it showed 67% (24.4 kN) improved performance compared to steel. In the static bending test of the door assembly, the initial average reaction force increased by 25% compared to the steel, and the performance of all FMVSS-214 regulations was satisfied. The replacement of GFRP impact beams resulted in a 30% weight reduction

• The korean journal of orthodontics
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• v.36 no.2 s.115
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• pp.125-135
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• 2006

The purpose of this study was to measure and compare the level of frictional resistance generated from three currently used ceramic brackets; 1, Crystaline $V^{(R)}$, Tomy International Inc., Tokyo, Japan; 2, $Clarity^{(R)}$, 3M Unitek, Monrovia, CA, USA; 3, $Inspire^{(R)}$, Ormco, Orange, CA, USA; with composite resin brackets, Spirit, Ormco, Orange, CA, USA; and conventional stainless steel brackets, Kosaka, Tomy International Inc., Tokyo, Japan used as controls. In this experiment, the resistance to sliding was studied as a function of four angulations $(0^{\circ},\;5^{\circ},\;10^{\circ}\;and\;15^{\circ})$ using 2 different orthodontic wire alloys: stainless steel (stainless steel, SDS Ormco, Orange, CA, USA), and beta-titanium (TMA, SDS Ormco, Orange, CA, USA). After mounting the 22 mil brackets to the fixture and $.019{\times}.025$ wires ligated with elastic ligatures, the arch wires were slid through the brackets at 5mm/min in the dry state at $34^{\circ}C$. Silica-insert ceramic brackets generated a significantly lower frictional force than did other ceramic brackets, similar to that of stainless steel brackets. Beta-titanium archwires had higher frictional resistance than did stainless steel, and all the brackets showed higher static and kinetic frictional force as the angulation increased. When the angulation exceeded $5^{\circ}$, the active configuration emerged and frictional force quickly increased by 2.5 to 4.5-fold. The order of frictional force of the different wire-bracket couples transposed as the angle increased. The silica-insert ceramic bracket is a valuable alternative to conventional stainless steel brackets for patients with esthetic demands.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.2
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• pp.89-95
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• 2003

Propulsion system of the current developing satellite is roughly composed of propellant tank and four major modules. Each module prevides the pulse momentum for spacecraft attitude control, filling/draining of propellant and pressurant, propellant filtering, and the change of flow passage in the spacecraft emergency situation, respectively. These modules will be fixed on the propulsion platform with their suitable mounting brackers, so the brackets shall be designed sufficiently to support a function of the modules under launch environment and on-orbit condition. The purpose of this article is to check if all the bracket designs satisfy the defined structural requirements through finite element analysis, and then to verify structural safety.

• Proceedings of the KAIS Fall Conference
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• 2001.11a
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• pp.104-106
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• 2001

This paper presents the usage of software package APM WinMachine for design of train car elements. APM software uses fur maximization of design productivity and efficiency in designing and evaluation machine elements and systems and CAD modeling. In process of machine designing needs make strength calculations of machine parts with complecated design. Will the help of APM software strength calculations can be done quickly. On the Demichovo machine-building plant with the use of APM software were made quickly and effectively strength calculations of the cradle of the suspension of air-conditioner of car train and the mounting brackets of a tank of train toilet.

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.2
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• pp.51-56
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• 2006

Use of products containing phytoecdysteroid (PE) as active principle has become popular in prominent sericultural areas of India for hastening larval maturation events and synchronizing cocoon spinning activities as an obvious advantage is assured. At times, the present recommendation of administering PE at the onset of spinning results in peak labour requirement at odd hrs. To enable making recommendation for the use of PE on $multi{\times}bivoltine$ silkworm hybrids based on the climatic conditions prevailing in different areas especially with regard to temperature, the experiment was taken up to determine proper treatment times so that the induced spinning will be more orderly and the labour can be leveraged more efficiently. Different brackets of low ($18-22^{\circ}C$), medium ($24-28^{\circ}C$) and high ($29-32^{\circ}C$) temperature were simulated during the latter half of V larval instar and cocoon spinning. PE was administered to $multi{\times}bivoltine$ silkworm ($BL67{\times}CSR101$) hybrid batches as per the recommended dose at three different times viz., 10 am, 4 pm and 10 pm. Three replicates of 100 larvae were maintained for each treatment. Absolute controls were also maintained in each temperature range to compare the results. Cumulative maturation percentage was recorded at 6 hrs interval to ascertain peak mounting span. The influence of the treatment on the cocoon traits also was studied. Based on the peak mounting span, it was evident that in low temperature 10 pm treatment would be better. In medium and high temperature, treatment at 4 pm proved to be a better option. The influence of the treatment times at different temperature range on labour management is discussed.

• The korean journal of orthodontics
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• v.36 no.3 s.116
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• pp.198-206
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• 2006

With the introduction of the xenon plasma arc curing light and the LED curing light as orthodontic curing lights, the polymerizing time of orthodontic composites has clearly decreased. In contrast to various research cases regarding the polymerization time and bond strength of the xenon plasma arc curing light, not enough research exists on the LED curing light, including the appropriate polymerization time. The objective of this research was to compare the bond strength of the plasma curing light and the LED curing light in regards to the polymerization time. The polymerization time needed to achieve an appropriate adhesion strength of the bracket has also been studied. After applying orthodontic brackets using composite resin onto 120 human premolars, the plasma arc curing light and the LED curing light were used for polymerization for 4, 6, and 8 seconds accordingly. This research proved that the LED curing light provided appropriate bond strength for mounting orthodontic brackets even with short seconds of polymerization. The expensive cost and large size of the device limits the use of the plasma arc curing light, whereas the low cost and easy handling of the LED curing light may lead to greater use in orthodontics.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.6
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• pp.353-358
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• 2018

In this study, it is describe to an optimization analysis process for the weight reduction of the voltage converter in the electric vehicle charging systems. The optimization design is a technique that finds the optimal material distribution under a given material quantity constraint by combining the design sensitivity with the material properties and the mathematical optimization. Among the topology optimization, a lightweight design is performed by a solid isotropic material with penalization with simple formula and well-convergence. The lightweight design consists of three steps. As a first step, a finite element model for the basic design of the on-board voltage converter was constructed and static analysis was performed on the load. In the second step, the optimum shape is obtained for the lightweight by performing the topology optimization using the solid isotropic material with penalization applying the stiffness coefficient of the isotropic material to the static analysis result. As a final step, impact analysis was performed by applying a half-sinusoidal pulse shape impact load which satisfies the impact test standard of the vehicle-mounted part with respect to the optimum shape. In the topology optimization, the design domain was defined as the mounting bracket area, and the design technology was finally achieved by optimizing the mounting bracket to achieve a weight reduction of 20% over the basic design.